The utilization of radionuclides in the diagnosis, management and treatment of disease constitutes the field of Nuclear Medicine. As new techniques and methods become available, emphasis in research and application changes. The use of radionuclides for imaging and functional studies remains the bulwark of routine clinical use. However, increasing interest in non-invasive in vivo determination of function and metabolism has given new direction to the synthesis of organic radiopharmaceuticals labeled with positron-emitting nuclides of short half-life. A parallel development in the field of instrumentation, i.e., the positron emission tomograph, several models of which now exist, requires suitably labeled organic radiopharmaceuticals for its full realization as a new tool for the diagnosis of human malfunction and disease. Our program focuses on developing new organic radiopharmaceuticals labeled with positron emitting nuclides such as carbon-11, fluorine-18, nitrogen-13, and oxygen-15 and on labeling analogs with halogens such as iodine-123. All applicable synthetic methods will continue to be developed. Efforts in maximizing yields of carbon-11 and fluorine-18 via charge particle reactions have led us to begin automation of production and assay of synthetic precursors (11CN, 18F-F2) with special emphasis on methods which are readily applicable in medical cyclotrons. A concomitant purpose is the training of personnel at the graduate and postdoctoral level in accelerator work. Specific aspects of our program include: development and use of anhydrous 18F-F2 in labeling; biological stability of C-18F and C-123I bonds; extension of the synthesis and use of compounds such as 18F-2-fluoro-2-deoxyglucose as glucose metabolism probes in brain and heart and tumors, organic amines labeled with carbon-11 and nitrogen-13 as enzyme level probes in the lung and other organs; and application of simple non-synthetic methods to a wide variety of potentially useful radio tracer. The recently acquired positron emission tomograph will in concert with this program allow us to develop and exploit a complete range of compounds labeled with positron emitting nuclides. Technology transfer at all levels from nuclide preparation to medical application will be one of the cornerstones of our effort.